Electric mine lamp



NOV. 26, 1929. J, G, DALOZ 1,736,997

ELECTRIC MINE LAMP Filed June l1, 1926 2 Sheets-Sheet l Nov. 26, 1929. J. s. DALoz ELECTRIC MINE LAMP Filed June 11. 1926 2 SheeliS-SI'leei*I 2 nw f,

f @YM Parental Nov. 26, 1929 UNITED STATESIQPATENT ori-Ice A JULES GASTON DALoz, or COURBEVOIE, FRANCE -V ELECTRIC MINE LAMP.

Application led June 11, l1926, Serial Nat115,172, and in Francej'une 24, 1925.

This invention relates to4 electric mine lamps and particularly to those of the type in which the lamp is enclosed in a safety globe containing iuid under pressure.

5 The invention` is applicable to all such lamps, but particularly to those of the portable type equipped with batteries.

One of the objects of t-he invention is to provide a. safety globe in which the fluid under pressure need not be constantly supplied as in prior art devices, but in which the pressure fluid is maintained as long as the lamp functions properly or until certain agencies to be described modify its func- 'tioning.

Another object is to provide means for maintaining the lamp Adimply lighted after pressure fluid has escapedl from the safety globe, the degree of incandescence of the filament being modified so that, in the event of breakage of the lamp, there is vno danger of explosion of any mine damp that may be present. v y

A further object is to provide a mine lamp detector in connection with the lamp so arranged that the fluid under pressure in the safety globe escapes in the presence of dangerous gases and either extinguishes the lamp or modifies its luminosity.

A still furtherl object is to provide means for charging the lamps with pressure fluid, said means being especially designed to coact with the pressure maintaining device of the safety globe. I

Other objects will appear in the following detailed description and the drawings in which 1 Fig. 1 is a vertical section of a portable electric mine lamp with a battery, embodying the invention and showing the top portion of the battery and the lamp proper. The safety globe is here shown in its uncharged or discharged position'.

Fig. 2 is a horizontal section taken on line 2-2 of Fig. 1.

Fig. 3 is a vertical section through another form of lamp especially designed for attachment to a miners hat. This view shows the safety globe charged with pressure fluid.

Referring to Fig. l of the drawings, there l globe with is shown a cylindrical shell a having an upper threaded portion a2 adapted to screw into the internally threaded cover member Z serving as support for the lamp proper. Shell a is designed to receive a battery a1 fitted with 55 sprlng supported terminals a3. The lamp proper comprises a safety globe c having a termlnal annular flange adapted to. be clamped'between an annular flange formed on cover member d and the platform forming t-he base of the lamp by means of an annular externally threaded member e. The globe is clamped between gaskets f which serve-as cushions between the contacting surfaces on each side of globe c and also to hermetically seal the latter. The platform forming the base of the'lamp comprises: (l) elements serving to conduct current to and from the lamp; (2) elements for charging the safety gas and for maintaining the gas 7u under pressure therein; and (3) elements forming an elastic switch for diminishing the lumlnosity of the lamp when gas escapes from the safety globe.

The elements in the lamp base for conduct# ing current to and from the lamp are two contacts g imbedded in an insulating disc b, a central cylindrical conductor z'l which carries current from one of the contacts g to one of terminals of the lamp, and shell la, h1 which s0 serves as peripherical support for the lamp and is connected to the second of the two coutacts g through diaphragm switch j and Pin g1,

The elements cooperating to maintain the gas pressure in globe c and for charging said globe are similar in design to gas valves used for performing the same function in pneumatic tires. There is a valve i fitted with a stem which, on being opened, communicates through orifices h and o formed in the lamp supporting members with safety globe c. The lamp supporting member la. is provided with a horizontal extension or i-ange h1 which is made as large as possible in order to guard against 'gas leakage. The valve seat for i consists-of a member having a large upper cylindrical portion, a shoulder, and a lower,partially threaded cylindrical portion 1. The upper cylindrical portion 100 is perforated by hole ko and is internally threaded at its upper end to receive an annular threaded member '11* which serves to clamp metallic cap e" in position against the action of spring is( valve seating member is insulated from. h, h1 by insulating disc 3 which serves at the same time as, or is combined with a gasket for preventing the escape of gas. The threaded portion of il is in engagement with one of the contacts g, and, by means of nut i2, co-

operates to hold the whole assembly firmly;

together. 'The lower end of 'il presents asmooth outer surface i? adapted to coact with the apparatus for charging the safety globe.

The diaphravm switch comprises an elastic diaphragm j fitted into the lamp base and contacting along its periphery with flange h1. The diaphragm is responsive to changes in pressure obtaining in globe c and isdelected against the action of spring jl, which tends to oppose said pressure. A threaded pin g1 carries current from one of the contacts g to the chamber containing the diaphragm and makes contact with the latter' as long as the gaseous pressure is sufficiently high.

In the modification s hown in Fig. 3, designed for use with a miners hat, the above described elements are arranged in a somewhat diferent manner. The elements servin'g to conduct current to the lamp, for charging the safety' globe and for indicating the release of pressure fluid from said globe, instead of being combined into a unitary structure forming the base of the lamp as in the embodiment shown in Fig. l, arehere distributed between the lamp base and a second structure connected to the latter by proper conduits and wires and forming the cover for the battery shell.

The lamp base, in this modication, comprises an insulating disc m having a perforation therein'and carrying a lamp support and a central contact bothheld in place by screws n forming the terminals for inliowing and outiiowing current. The rest ofthe elements included in the lamp base shown in Fig. l are here assembled in the cover structure for the battery receptacle. This cover structure comprises an insulating disc b, a gas charging assembly z', 1, '152, 4, 7 more or less similar to the one already described, a pair of contacts g on one side of the insulating disc connecting with terminals Z on the otherv side'of said disc, a diaphragm switch j, il, g1 similar to the one described and finally a perforated disc lc, which serves the same function as flange h1 in the modification shown in Fig. 1. The above assembly isheld in place in cover member d by an annular externally threaded member e. Cover d is formed with a pair of hollow extensions adapted to receive a pair of flexible tubes p which form a means of gaseous communication between the cover and the lamp and, at the same time, carry The shoulder of the `holes at its upper part.

is preferably packed some such heat insuleads o from terminals Z to terminals n. The

lamp baseI m forms a wall between a rear chamber of thelamp g1, which communicates through the flexible tubes p with the cover (l, an a forward chamber Q2 which carries the lamp and-serves as a safety globe. The wall of the forward chamber g2 is formed by 4an annular shell g which serves as a support for the front glass window, and for the elcments for holding the latter in place.

In the construction shown in Figs. l and 2, or that shown in Fig. 3, the operation of the apparatus remains the same. In either'type of lamp structure, the latter may be charged taining the lamp dimly lighted after the gas' pressurehas diminished to any predetermined value. Where the lamp is arranged to remain dimly lighted, its luminosity should be diminished sutticiently to avoid danger of explosive mine gases becoming ignited. in the event of breakage of the safety globe and of the lamp proper. The lamp should, however, furnishenough light to indicate its position.

The supplemental structure for maintaining the lamp dimly lighted after partial or total escape of gas from the safety globe is indicated in connection with the form of apparatus shown in Figs. 1 and 3 and includes a spiral resistance wire 1' interposed between diaphragm y' and pin g1.' The resistance thus arranged is short-circuitcd when diaphragm j contacts with pin g1 i. e. when the gas pressure is suflicient to light the lamp. When gas escapes and diaphragm j breaks contact with pin g1, current will continue to flow to the lamp through resistance r. The resistance fr should preferably be adjusted to give a filament temperature less than 650 C.

The mine damp detector is shown in connection with the form of apparatus illustrated in Figs. 1 and 3 andincludes an escape conduit C, preferably in the form of a truncated cone, sealed with some easily fusible -substance like wax, A, surrounded with-a mass of catalytic material, such as sponge platinum B, locatedin a chamber, preferably formed by a glass sphere F silvered internally and having a large aperture at its bottom and little The latter chamber lating material as cotton wadding G which holds the said chamber in position over the mass B. A wire screen H permits entry of the mine ases into chamber F, these gases being con uct-ed to the said screen by means of the cap D which issuitably formed and connected with the cover member d' in consequence. f

Preferably the whole of the detector is arranged in such a manner that it may be readily changed but only by authorized persons. This may be performed in making said whole detachable when a safety device, such as a magnetic is operated, or by providing lead rivets E3 as shown in the drawing where the chamber F-is enclosed in a cap E1 screwed in an upper extension E of the main cap D, a gasket E2 being interposed between flan'ges of E and El.

rl`he manner in which the device operates is as follows: If the lamp is burning in an atmosphere having too high a concentration of mine damp (methane, ethane and the like), these gases will penetrate through screen H and wadding G to sphere F where they will come into' contact with the catalyzer B. The gases, in coming in contact with the catalyzer, will liberate enough heat to melt the fusible seal A. As soon as this seal melts, the gases held in safety globe c will escape through conduit C, thus releasing the pressure on diaphragm j and immediately reducing the luminosity of the lamp. The gas in globe c is preferably carbon dioxide, which, as is well known, is non-inflammable and which when used in the present connection serves to prevent all danger risks. Wire screen H prevents the possible spread of flame from sphere F to the atmosphere outside the lamp.

It is to be understood that the apparatus may be' made up with or without the mine damp detector or the dimming attachment and that other charging apparatus may be used in connection therewith than that herein shown and described.

Similarly other sources of current than a battery may be utilized for supplying the lamp or lamps, as for example terminals connected to wires leading to a prime mover situated remotely from said lamp or lamps.

Furthermore, the parts of the invention concerning respectively the dimming means, the detector and the wires surrounded by cone duits for fluid under pressure may be utilized on other lamps with a security device under control of a fluid under pressure, all this without departing from the spirit of the invention.

What I claim is 1. An apparatus of the class described comprising in combination a source of current, a lamp, a chamber enclosing said lamp, means for sealing a fluid in the space between the lamp and the walls of said chamber, a fleX- ible diaphragm communicating with said space, said diaphragm being connected to one terminal of the lamp socket, a Contact lead- 'the diaphragm ilexes against the contact and ing to the current source, and a resistance Wire connecting said diaphragm to said Contact, the diaphragm, the contact and the resistance Wire being arranged so that, under pressure current flows directly from diaphragm to contact, and, on release of pressure, the'dia- I yphragm moves away from said contact and current flows from diaphragm to contact through the resistance wire.

2. An apparatus of the class described comprising in combination a source of current, a lamp, a chamber enclosing said lamp; means for admitting pressure fluid into the space between the Walls of said chamber and the lamp, a pressure sensitive switch communieating with said space, and means operable by combustible gases to release the pressure on said switch.

3. An apparatus of the class described c omprising in combination a source of current, a lamp, 'a chamber enclosing said lamp, means for admitting pressure fluid into the space between the lamp and the walls of said chambers, means for modifying thefloW of energy to the lamp with change of pressure in said space and means operable by combustible gases to release the pressure fluid from said space.

4. An apparatus of the class described comprising in combination a source of current, a lamp, a chamber enclosing lsaid lamp, means for admitting pressure fluid into the space between said lamp and said walls of said chamber, means for modifying the supply of energy to the lamp with change of pressure in said space, a pressure fluid outlet tube communicating with said space and sealing means for said outlet tube comprising a substance Whose temperature is modified in the presence of combustible gases and a substance of low melting point.

5. An apparatus of the class described comprising a first unitincluding a lamp, an enclosing chamber for said lamp, a base for sup- 1 10 porting said lamp, said base carrying the lamp terminals and having an orifice therein; a second unit including a cover member, a disc hermetically closing the bottom of said cover member, said disc comprising means for carrying current therethrough, means for passing gases therethrough, means for modifying the flow of current therethrough; and a flexible hose enclosing electrical connections leading from the first unit to the secy tube comprisilfg a metal of the platinum A grou and a substance .of suiciently low melting point to liquefy'under the action ci the heat given o b contact of combustible 5 mine gases with sai metal.

y7. An apparatus of the class deined comev prising in combination a chamber adapted to contain a fiuidunder pressure, me'ans for niaintaining a iiuid under pressure in said chamber, pressure indicating means adapted to indicate changes 'of pressure in saidchamber,`and means operable by 'a combustible J' mine gas to release Huid under-pressure in said chamber and to thereby actuate said pres\`` sure indicating means.l

In testimony whereof I hereunto aix my signature.- .f

JULES GASTON DALOZ. 

